ps -ef | grep newrelic-daemon
Should print three processes such as :
colin 3091 4221 0 21:51 pts/0 00:00:00 grep newrelic-daemon
root 17881 17834 0 21:46 ? 00:00:00 /usr/bin/newrelic-daemon --agent --pidfile /var/run/newrelic-daemon.pid --logfile /var/log/newrelic/newrelic-daemon.log --port /tmp/.newrelic.sock --tls
root 17902 17881 0 21:46 ? 00:00:00 /usr/bin/newrelic-daemon --agent --pidfile /var/run/newrelic-daemon.pid --logfile /var/log/newrelic/newrelic-daemon.log --port /tmp/.newrelic.sock --tls -no-pidfile